BMW V8 dry sump from billet

[Artie]

Ade, dont forget this is the scavenge side of the pump, oil cannot leak unless the engine is turned off. dont fret too much about oil tightness, it isnt an issue as what oil there will be, when shut down, will only be 'pooled' and will only seep, and only then if you have a major issue. Leak gone as soon as you start the engine. Also

With the intererence fit and suitable loctite this will never move (not even when you want to!) chech out www.loctite.com. The temps you mention are not extreme for the average loctite product, dont forget they are designed to work in an engine environment, particularly the racing environment.

Personally I would go with the flat plate bolted on the end because after an engine blow (it happens) you are going to have to be able to clean out the galleries, plugged as you describe would make this a difficult job.

Refer to the comments above, this is not a high load hydraulic joint, it is a slight vacuum joint. A plate with 3 o rings would be much much more than is needed. # staggered height Earls 90 degree fittings would give you the clearance you need.

Cheers  Artie

[Darren]

You can still separate the plugs for more room, a plate wouldn't affect that.

I just feel a plate clamped down by say four bolts with a ptfe or other gasket would be the safest and easiest all round. Just a rectangular plate and gasket. As Artie says, you can then pop the plate off to clean it all out at a later date.

[DMIOM]

You can still separate the plugs for more room, a plate wouldn't affect that.

I just feel a plate clamped down by say four bolts with a ptfe or other gasket would be the safest and easiest all round. Just a rectangular plate and gasket. As Artie says, you can then pop the plate off to clean it all out at a later date.

yes, to look it another way - its just an extension of the sump. Engines often make do with one of pressed tin with just a cork or card gasket ....

[andyf]

Just a thought - if using plugs, might it be a good idea to drill and tap blind holes in them at this stage, to make extraction easier if/when you ever need to get them out?

Andy

[AdeV]

Interesting thoughts chaps.... can someone do a C-o-C of this plate idea? I'm assuming that it works as per the below (please excuse the ASCII-CAD):

  ]-_T-------
  ]-+-_T-----
  ]-+-+-_T---
    | | |
    | | |
    | | |


Key:
 | = cross-drilled pipe
 _T = cross-drilled pipe meets end-drilled pipe
 - = end-drilled pipe
 + = cross-drilled pipe crosses end-drilled pipe
 ] = plate bolted on end of sump

i.e. at the point of intersection, all three pipes are inter-connected?

[crankshafter]

Hi Ade.
Been sort of quiet for some time. Where are you hiding? in piles of wax I think
Me /we need some update on your great project.

Crankshafter

[AdeV]

I've been putting it off (see the keypad thread), because it's time to move to aluminium.... but before I start cutting I need to clean & tram the mill... so that'll be tonight's job, now that the keypad is done & I can't procrastinate any further!

Hmph, 3 hours of cleaning and tramming.... no cutting tonight, you'll have to wait until tomorrow.... 

[AdeV]

Right. The adventure begins again, hurrah!

First, I lobbed the aluminium onto the mill, got it reasonably square & in a position where the cutter can reach all four sides (not sure about the tabs, I think they're still out of reach, just). Milled some straight/square/smooth "index surfaces" onto the front corners; I can now use these to set my reference points:



You can see the index surface, near the "0,0" legend (which, thanks to my very expensive medical education*, looks more like "p,v" in the photo). Current width is, approximately, 261mm. I'll remove 6mm from one side & 5mm from the other, to make best use of the tabs later on. The full length is 560mm, I'll take as little as possible from the front edge (just enough to make it square), the remainder from the back edge. The reason, again, is due to those tabs; because the piece was cut out of a disc, there's an angled edge on the front tab, I need to maximise the overall width there as best I can, so I don't have to make an add-on piece later. It's tricky to explain without a crap-o-cad... maybe I'll do one of those tomorrow instead of working...


I found a use for the memofix too (well, I read it in the manual): Flick the memo switch to "stop when you get to the index mark and act all broken", move the table until x & y lights are lit, and write the numbers down (you can see them near the left-hand clamp). Now I can power off the mill as often as I like; when I start up again, just flick the memofix switch to "broken", move the table until the lights come on; type the numbers into the DRO & put the memofix switch back to "working": And presto, as the table crosses the index mark, the counter resumes. So now I don't have to edge-find every time I power the mill off. Nice one, Dr Heidenhain!

Tomorrow: some cutting







(* OK, I lie, I never had an expensive medical education. I just write like a doctor. Very very badly...)

[zeroaxe]

(* OK, I lie, I never had an expensive medical education. I just write like a doctor. Very very badly...)

It is a good thing then that you are writing this project on the comper!!! 


Btw, GOOD JOB!!!!

[John Stevenson]

Ade,
Do you have the horizontal attachment for the Bridgy ?

John S.

[Brass_Machine]

Looking forward to seeing your dry sump made out of aluminum. Got a kick out of it in wax... gave me the idea to try some of the complex stuff I want to do that way first! Good job on that... now onto the real thing.

 

Eric

[AdeV]

Zeroaxe - it certainly is, but my typing is appalling too - but having typed pretty much daily for over 25 years now, I make & correct mistakes really fast Incidentally, you should probably know that, about 6 months ago, I didn't have a mill, lathe, or any machining experience whatsoever... I'm still learning like crazy, and for all it's size, this sump is actually relatively simple.

Do you have the horizontal attachment for the Bridgy ?

John - I've got the #4 right-angle drive (the small one that takes unobtainium collets), and have recently picked up a Quillmaster + right-angle attachment; but the beefy #3 right-angle drive + arbor + support has so far proven to be beyond my meagre financial means. I'm guessing you're going to suggest that it would make light work of trimming this piece to size, and I'd be tempted to agree (although I'd need some pretty large diameter cutters). One day, I will have the #3 head, at which point I'll sell the #4 on, as any work it can do can be done with the Quillmaster instead.

Eric - The wax version certainly taught me a lot about what I'm trying to do; and has given me a good idea about what order I should be doing the machining operations in; and also which operations to avoid (that 2mm "pocket" which caused so much grief with the angle plate, for example). I'm not finished with the wax yet, I still have to profile the back of the sump, and I'll do that in wax before I do it in the aluminium.

[John Stevenson]

OK then no head.
What I was going to suggest was, if you had the #4 head you could spin the ram over so it was at one end of the table, fit the head and line it up parallel to the bed and then when you drill you will have the plate better supported because you have most of the bed not being used up with the head located over it.


John S.

[zeroaxe]

Btw, what you mentioned the other day about drilling holes right through the Ali to have reference points once you turn it over..., and this way loose a lot of WD40 'draining' through to the bottom..... I thought of something that you might be able to use(might work, might not) for the next time. Drill your holes through just like you did, and then shove a wooden dowel in the hole to (re)block it up.....? Makes sense?

[AdeV]

John - not a bad idea; it would also mean I could be sure that the drill was parallel to the table (to the best of my tramming abilities), wheras with the head canted over I have to try to get everything lined up perfectly, without any really decent tooling. I'm open to ideas on that one.

Zero- makes perfect sense (doh). Having said that, I'm done with the 6mm cutter (for now, at least), so it's not currently a worry, but thanks for the suggestion 

OK, on with the show. Another 4 hours in the shop, started like this:



That's a 4.5mm cut with the 12mm rippa cutter (ebay link - buy one, they're ace). I sliced down in ~1cm depths at around 250mm/min feed rate until I had to lower the cutter in the collet. After that I went at 1/2cm DOC, just to reduce the strain on the cutter. I've only got one 12mm cutter, didn't want to break it.

After roughing out, take the final 0.5mm in 4 passes - top & bottom, 0.25mm at a time - using a 20mm 4-flute cutter (the only one I've got deep enough to cut the whole depth, with the flatted section inside the collet):



Repeated this on the backside, and the end (I had to move the clamp again, quelle surprise. One day I'll clamp the bugger in the right place the first time).

So, here it is, looking almost exactly the same as it did yesterday.....:



But now it's the right width, compared to the wax version:



Saturday tomorrow = all day in the shop 

[AdeV]

Just an aside, you can probably see a slight shadow under the block, most noticably under the clamps. I've got it sat on some parallels, so I can drill full-depth holes without having to stop the drill short of breaking through 

[jim]

i awiat tonights update!

[AdeV]

Wait no longer... for tonight's update is here

It was supposed to be a short one. Just 2 or 3 pictures to show the progress, and a few words to liven things up. But no, for today we had the first f**kup...

Aaaaanyway, I decided to start by spotting & drilling all of the perimeter holes, like I did with the wax version. Things went well, until.... heart attack time!



I've just run the drill from the last hole on the back edge of the sump, up to the front edge - but what's this? The drill is a good 1cm from the hole? Then it dawns on me.... the front & back edge holes aren't in line on the engine. Muppet! Just to re-assure myself, I measured it all up again & yep - it's bob on.

However, if you look to the top(ish) right of the photo, you'll see the cockup, which occurred somewhat earlier. Here it is a bit closer:



The one, and pretty much only, real "gotcha" on my mill, is the fact the quill return spring is broken (and, as it happens, completely missing) As a result, I have to use the quill lock at all times. And I have to make sure I've used enough force when applying it to make sure the quill stays put. When I fail to do that, the result is what you see above - about a 4mm deep gouge where the drillbit dropped back down just as I started cranking on the X-axis to move to the next hole. How the drill bit didn't snap or bend, I have no idea - but it survived to drill another dozen plus holes.

Anyway, as a result of that, I've decided that the top 5mm will be skimmed off the entire piece of aluminium, so all vertical measurements now have to be +5mm. I hope I remember that all the way along...

So, the next operation, mill out the oil drains. There was a 1mm measuring error in my original diagram (and, therefore, on the wax prototype). I double-checked it on the engine and yes, I had measured it wrong originally. Fixed it for the real deal:



I've only taken them 10mm deep for now, I'll come back to them later. And, finally for tonight, mill out the first of the central pockets - some 100mm long by 75mm wide and 30mm deep all told:



I started out by slotting out the perimeter with a 6mm rippa; but after I killed two of them, I switched to the 12mm. In the end, the radiused edges aren't that bad, so I'll save my remaining 2 6mm rippas for another day:



I cut the pocket 1mm undersize all round with the 12mm ripper cutter, and finished off with a regular end mill. Although the surface in the bottom of the pocket doesn't look that hot, it's actually remarkably smooth; with only one ridge I can feel in the whole lot. Must have got that tramming about spot on, then

Tomorrow: Finish the pockets off, and - if there's time - get the mill set up for the deep drilling... heck, maybe even drill one of the holes!

[Divided he ad]

Your a brave man Ade!!!   


Good luck with the rest 


Remember measure 43 times cut once!   


Well that's what I usually do..... Still chicken up much of the time though!!!*   









Ralph.






*_{(words have been changed to protect the innocent!)}

[jim]

keep up the good work!!!

[Stilldrillin]

Looking good Ade! 

May good luck stay with you...... 

David D

[kvom]

FWIW, roughing out the pockets by drilling may save some time vs. milling.  And it will save the endmills.

[AdeV]

Funny you should say that Kvom - I did wonder about making lots of drill holes, but in the end I settled for spotting & drilling the corners of each of the remaining 3 pockets. I drilled them to the biggest drill the little Albrecht will take, 10mm.

Here we are after the spotting work is done (including some idiot lines), but before I drilled out the holes:



After that, it was just a case of mill, mill & mill some more. Each pocket is 3cm deep, 75mm wide, and either 81 or 102mm long. Using the 12mm roughing cutter, going 0.5mm undersized all round, and taking 5mm deep stripes, eventually I had all 3 holes dug. To finish, I went around each hole twice with a regular end mill, opening out to the full size, then cutting back & forth across with 0.025" depth of cut to get to the final 3cm (sorry about the mixed units, the knee is in inches, as is my depth mike. In the end, I missed my depth by 0.002", but frankly life's too short, and it's not a critical dimension.

Here's one of the finishing cuts going on. I did all the finishing under oil:



Some wax offcuts do service as crude spray shields. Each pocket is milled in the classic English Lawn Style (i.e. stripes), which reduced the number of full-width power-fed cuts to just one per pocket per 5mm.  So, after many hours (including an extended break for taxi duties):



It may not look much, but the surface at the bottom of each pocket is some of the best surfacing I've ever achieved with a regular end mill - it's absolutely perfectly smooth to the touch. I'm not sure how many tenths of imperfection you can get away with before you can feel it, but I know it's less than a thou. So, it's a shame it's going to be hidden away under the oily bits of the engine (actually, most of it won't even survive to see that.... it gets milled away when I make the slope down to the drain holes). Ho hum. 

PS: No cutters were harmed during tonight's production 

[Divided he ad]

Now that's looking nice   



You must have been there for hours?



Good to see it all going to plan 





Ralph.

[Brass_Machine]

I agree with Ralph... looking nice!

Can't wait to see it finished.

Eric